Electron discharge device



Sept. 21, 1943. DAlLEY- ELECTRON DISCHARGE DEVICE Filed Oct. 9. 1941 Y E N R O n A Patented Sept. 21, 1943 UNiT-ED STATES raven r orricr.

ELECTRON DISCHARGE DEVICE 1 Hampton Jennings Dailey, Bloomfield, N; J., as

Signor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporationof Pennsylvania Application ema- 9, 1941, Serial Ne. 414,227

' r7 Claims. (clam-27.5)"

This invention relates to electrondischarge devicesand particularly to means and methods of outgassing the grid forming an integral .part of such device; I 4

In the prior art, outgassing of 'a grid has been 1' accomplishedin one of several ways..v For in stance, the gridhas been rendered incandescent by means 'of an induction current applied thereto while the electron discharge device is in the process of being evacuated. Such a method has certain drawbacks, amongst which may be mentioned the difiicult or even the impossibility of induction-igniting the grid wherethe anode of low resistance material, such as copper, forms, part of or forms the entire envelope containing:

the other triode electrodes. Another method of outgassing the grid has been to pass .a heating current throughthe grid wires and thereby render those wires incandescent while the discharge device is on the exhaust'machine. This again is, unsatisfactory or impossible inractual 'practice in many instances, particularly when the:grid has such'form that a continuous circuit is disrupted by presence of supporting wires or posts or other bracingv meansat intervals along the length of the grid wire;

A further. method of .outgassing a grid employed in the prior art has been the useof-electron bombardment obtained by heating the fila-' ment of the triodeand at the same time applying a positive potential to thegrid; This method likewise has its drawbacks, wher 'presence of close grid-to-filament spacings require relative.- ly heavy currents at. low voltages, which is detrimental to filament emissions a means and method of outgassing a grid 'overcoming the. difficulties encountered by prior'arl; methods. a

A further object of the invention is t o-out gas the grid oftriode electrode without detri ment to the other electrodes of such triad e11,

A further object of the inventionis to provide means and method ofoutga'ssing a gridandin ion bombardment of #15 doing so to avoid excessive the triode cathode. I p y A still further object of the'invention is to numerals ofireference indicate similar parts,

throughout. the several views, and wherein preferred embodiments of the invention are disclosed y Way of example; 7

Figure 1 is w Partially in elevation and partially in longitudinal section showing an elec- Anobject of thepresent inventionis to devise provide a means andfmethod available toelec' tron discharge devices utilizing metal containers or other shielding structure around the grid.

Still further objectsof the invention will ape pear to those, skilled in the art asthedescription progresses, both bydirect statement thereofand by implication from the context. r

In the accompanying drawing, wherein like the particular transmitting tron discharge device, inclusive of its envelope, embodying the'present invention in-its preferred construction;

Figure 2 is a cross-sectional View on line 'IIII I of Fig; 1-;

:Figure "3 is a a modified arrangement of circuits;

In the specific embodiment of the inventionillustrated in said drawing,- a part: of a triode electronic discharge device generallyidentified 1 as a transmitting tube, is depictedexemplifying"- the invention as part thereofr; Itshouldbe 111 derstood, however; at the outset; thatathe inventionis applicable to other electronic devices than tube here selected for illustrative purposes.- i

The specific tubeishown comprises a glass or other ceramic bowl l0, .here. represented as part 3 of an evacuated envelope,.and as also constituting the base portion fun the device, for-which purpose it-is equipped with appropriate prongs I l protruding from the. bottom thereof. These prongs are each preferably unifiedwith appropriate posts, such as I2, l3, and I4 shown in t:-Fig. 1, extending upwardly within; the interior of said bowl 'or base portion rlfl. ;At the upper rim of the bowl portion l0 there;is sealed into the glass or other ceramic a featheredge of-a connectingring-like portion l5 to a metal upper ,portion which in-part also constitutes the triode anode IS. A part-of the anode proper is shown re-entrant with respect to theconnecting rim or? ring por-tion l5, thereby providing an annular upwardly opening exterior groove 'l'l-serviceable in connection with cooling the anode in use. 1

tour of grid. Said gridis alsorshown as having a n t a o dwi e 2 ac i tof-crq s n view similar 'to' Figure 1 but of a somewhat diagrammatic nature, for indicating? the preferred electric circuit connections to l the" several electrodes and fabricating fila'mentyand- Figure 4 is a view similar-to Figure 3 showing currents applied will be effective upon the-triode filament only. k

By either embodimentof the invention, it, will now be apparent that the triode-grid may be outgassed with a highvolt'age low current bombard'-- ment but without subjecting the triode filament to ion bombardment during exhaust. It will also be observed that the construction and method described enables the grid to'have reenforcing wires as part thereof without interfering with the outgassing operation. Likewise, in bothconstructions, the fabricating filament is rendered ineffective by circuit interruption and thereafter. the triode electrodes function in their normal* capacities.

Since the various details of construction, as. well as the precise relation and functioning of parts are subject to variation and change without departing from the inventive concept orscope of set forth as a matter of language which might be said to fall therebetween. v

I claim: e

1. In an electron discharge device comprising an envelope and triode electrodes, namely, a cathode, grid and anode, the combination of a fabricating filament in addition to and associated with said triode electrodes in such relation therewith that the grid of thetriode constitutes an anode with respect'to, the said fabricating filament. e e I 2. In an electron discharge device comprising an envelopeand triode electrodes, namely, a fila ment, grid'and anode, the combination of a fabricating filament in addition to and associated with said triode electrodes in such relation therewith that the filament of thetrio-de constitutes a grid and the grid of the triode constitutes an anode with respect to the said fabricating filament.

3. In an electron discharge device, the combination of triode electrodes, namely, a filament, grid and anode each having a generally cylindrical formation with the triode filament surrounded by parts; of the grid and the grid surrounded by parts of the anode, and afabricating filament surrounded by parts of the 'cylindrical formation of said triode filament whereby said triode filament may function as a grid with respect to the fabricating filament.

4. In an electron discharge device comprising an envelope and triode electrodes, the combination of a fabricating filament associated with said triode electrodes in such relation therewith that an envelope andtriode electrodes including a filament, the combinationof a fabricating filament the grid of the triode constitutes an anode with respect to the said fabricating filament, said filaments having means for applying distinct heating currents thereto.

5. In an electron discharge device comprising an envelope and triode electrodes, the combination of a fabricating filament associatedwith said triode electrodes in such relation therewith that the grid of the triode constitutes an anode with respect to the said fabricating filament, said filaments having a common external connection and each having an independent connection to the other end of each filament for applying distinct heating currents to the two said filaments.

associated with said triode electrodes in such relation therewith that the grid'of the triode-con- I stitutes ananode with respect to the said fabri eating filament, said filaments beingconneoted inparalleland havingcommon external connections, said fabricatingfilament having a lower resistance and rendered incandescent with lower current than said triode filament. A

:7. In an electron discharge device comprising anvenvelope'and triode electrodes including a filament,- the, combination of a fabricating filament associated with said triode electrodes in. such relation therewith that the grid of the triode constitutes an anode with respect. to

the; said fabricating filament, said filaments being connected in parallel and ,having common external connections, said fabricating filament havinga lower resistance and rendered incandescent with lower current thansaid. triode filament' and said fabricating filament'being incapable of carrying current sufficient to render the triode filament incandescent whereby applying current to render the triode filament incandescent will burn out the fabricating filament.

8. The herein described method of outgassing the triode grid of an electron discharge .device 1 comprising utilizing the cathode of the triode as a grid, :applyinga positive potential to'the triode grid, producing an electron discharge through the'cathode acting as a grid, and utilizing said comprising producing an electron discharge, and

rendering said discharge effective upon the. triode filament as a'grid andupon the triode grid as an anode. I

10. The herein described method performed upon and in connection with an electron discharge device having a triode filament, grid and anode and a faloricating filament, comprising renderingthe fabricatingfilament electron emisthe triode grid of an electron discharge device, comprising supplying a cylindrical cathode, grid and anode to constitute said triode, supplying a stem within the cathode, supplying a fabricat- 12. A method performed upon and connection with an electron discharge device wherein said electron discharge device provides an en- I .velope and triode electrodes, namely a cathode,

and utilizing the grid of the electron discharge device as an anode and thereby obtaining a con- 6. In. an electron discharge device comprising trolledcleetren bombardment of: the grid by electrons from? said! auxiliary source 13 ."A@ method) performed upon and in! connec-- 1 tionwith are electron: discharge device: wherein.

said electron discharge device provides an; err-- velepei enclosing a cathode; gridzuanode and an:

auxiliary sourceaof, ele.ctrons',. said: method com prising: annlyin-gza potential: to-the cathode? posir tine'with respect to: the; auxiliary source of; elemtronsm applyinga.- znorei positive. potential: to the grid, and passing electrons from: the: said auxii' iary source? intoproximity; to saiii; cathode and thenceto! the said: gridctheneby bombarding said gridi by electrons: fromsaid'. auxiliary source? under controt exerted". by the cathode acting; as. a

14.. Aarnethod' performed upon and in connectinn an: electron. discharge: device wherein saith electronudi'scharge device provides an en' vel'ope enclosing a. cathode, grid, anode'and a fabricating. election emiiting filament, andwith which ans: provided external connections to said cathode-,1: grid; anode and: fabricating filament, said: method? comprising connecting the fabricating filament. to a source of electrical energy thereby causing: electrons to emit from said filamenir, applying aipositive potential: to theca'thode and a; morepositive. potential to the gridthrough their respective connections; therebyeii'ecti'ng' a controlled bombardment' of the grid-by'electrons from: thH fabricating fii'ament, and thereafterdisrupting the" circuit. of? external connection and fahricairh g: filament and. rendering the device usablecnly by electronsmission from the cathode.

l5. Amsthodi performed upon. and in connec tion withian: electron: dischargedevicewherein said' electron: discharge'devi'ce pi-ovides a triod'efilament,:gridt and anode and? a fabricating electromenrissive filam'ent and. circuit therefor, conmeeting). said fabricating filament through saidcircuit to a source of electrical energy, producing aeeoqoea that; the; grid of the. triode :mayconstitute. an anode with respect to the said fabricating file'- ment,. said. filaments. havinga" common:- external connection andi-eachhaving anindependent con- 5. mention to the other end: of each filament forepplying, distinct. heating: currentss to-the two said filaments-,. saidmethod comprising; applying a heating current to the connections for the fabricating: filament and heating said fabricating 1 0; filament causing: the same to\ emit electrons,. applying a positive-potentiali to thetriode filament andi a more positive potential tofithc. trio'degrid.

thereby constituting the: said triode. filament a grid: with respect to the fabricating filament and- 15. the triode grid an anode with respect to the fab ricating filament, and; thereafter" disrupting externalt GOHIIBBtiOII tOX the fabricating filament and requiring electron emission producing" currentto' beappliedi to the tri'ode filament.

A: method performed upon and in connecthin with an electron discharge device wherein said electron discharge device provides an envelopeenclosing triocle electrodes; namely, a tri'ode filamenta grid and an anode, and also enclosing a fabricating filament associated with said triode electrodes in such relation therewith that the grid of the triode may constitute an anode witlr respect to the said fabricating filament, said filaments being connected in parallel and having common external connections,'said fabricating filament having a lower resistance and rendered incandescent with lower current than said triocle filament and said fabricating filament being incapable of carrying current sufficient to render thetriode" filament incandescent, said method comprising applyinga source of current to the'common external connections for the two filaments of value within the current-carrying capacity vof. the fabricating -filament" and sufii'cient to render the same incandescent,,applying.a positive pot'entialito the tri'ode filament and a more positive, potential to the tn'ode grid thereby constituting the said tniode. filament a grid. andthe tri'ode grid an anode with respect to, the,fabricatingrfilament, and. there after. increasing. the current. to, the common external connections. for the filamentsv above the currentrcarrying, capacity of the fabri'cating,fila.

ment but within the current carrying capacity 50 ofv the tniodefilament thereby burning-out the fabricating. filamentand necessitating. the. current to. thereafter be applied to. the triode filament for operation, of. the device.

HAMPTON JENNINGS DAILEY. 

